1. Field of the Invention
The present invention generally relates to network file systems and schemes, and more particularly, to a network file system that appears to its clients to be a single file system, while locating its files an directories on multiple server computers.
2. Background Information
File system growth management is a large and growing problem for the data centers of eBusinesses and corporate intranets. Depending on the source, data storage is estimated to be growing between 60% and 200% per year and accelerating. According to the Strategic Research Corp., the two major storage-related problems in the data center are managing disk space and running out of disk space. Information Technology (IT) administrators are also struggling with placing their key, most important data onto the best storage resource in their environment. With the explosion in growth, IT users are looking for alternative solutions that simplify growth management.
The most complex issue involving the growth of storage is the inability to manage storage environments efficiently and with qualified IT professionals. eBusinesses today are facing an influx of new storage technologies (e.g., network-attached storage (NAS) and storage area network (SAN)), which increase their storage capacity, speed, and availability, but in ways have made storage architectures more complex. When new technologies are deployed, IT professionals must quickly ramp up and learn these new technologies, and with the current lack of skilled IT talent (˜600,000 unfilled IT positions today), falling behind is easy. In fact the cost of managing high-performance storage environments is estimated to be far greater than the cost of purchase—by three to ten times. The required ongoing investments in both hardware/software and people into these storage architectures will continue to rise.
In many enterprises, data is distributed among various “islands of storage,” which are cut off from each other by their means of attachment, physical location, management policy, or software incompatibility. These islands require applications to select and name the specific hard-wired server hosting the desired files. Typically, when applications outgrow their islands, IT administrators must bring down the applications, add new storage devices, partition and move some of the data, and reprogram the applications to make them aware of the new division of resources.
At the high end, customers can opt for SAN solutions, which are extremely expensive to purchase and maintain, and require a commitment to proprietary hardware. SAN architectures do allow for considerable scalability, flexibility and performance, but at a very high cost. A lower-cost storage solution is available: file servers. Network attached storage (NAS) devices and General Purpose File Servers (GPFS) provide interoperable, incremental, and somewhat scalable storage. However, each NAS device or GPFS sitting on a LAN has limited throughput. It is an island unto itself. IT departments have to statically partition their storage among these islands, which has a number of unpalatable consequences.